Biochemical challenges in future toxicological research.

Future biochemical challenges in toxicological research are discussed. The developed resistance of many insect pests to various commonly used insecticides is considered to be an extremely important problem. The need to develop new insecticides which are both environmentally safe and negatively cross-resistant with present insecticides is considered. The effectiveness of some pesticides can also be increased by the use of synergists. Synergists compete with the active substance at the detoxification sites and thereby reduce the effectiveness of the detoxification process. The effects of isomers, impurities, and metabolism products on the toxicity of various pesticides are presented. Finally, the need to further elucidate the mechanisms of action and selectivity of various pesticides is discussed.